Belt-tightener.



No. 776,170. PATENTED NOV. 29, 1904.

I'. P. BURKHARDT.

BELT TIGH'IENER.

APPLIoATIoN FILED nu 29, 1003.

Patented November29, 1904.

PATENT OFFICE.

FRANKLIN P. BURIUfIARDT, OF OHIOAG-O, ILLINOIS.

BEL"l"-TIGHTENEH.

SPECIFICATION forming part of Letters Patent No. "776,170, datedNovember 29, 1904.

Application led May 29, 1903. Serial No. 159,226. (No model.)

T0 (all 71171/6771/ 'llt uta/,y concern,.-

Beit known that I, FRANKLIN I. BURK- HARDT, a citizen or' the UnitedStates, residing at Chicago, in the county oi' Cook and State or'Illinois, have invented a new and useful Improvement in Belt-lightenersof which the following is a specification.

This invention relates to improvements in bclt-tighteners.

The object of the invention is to form a tightener which can be readilyadjusted by means of the ordinary tools carried with the machine and toform a simple practical device that does not occupy an objectionableamount of space at the point at which the same .is attached and whichmay be cheaply built and easily assembled.

The invention consists, substantially, in the construction set forth inthe accompanying;

specilication, and more particularly pointed4 .several iigures of thedrawing's, in which Figure l is a plan view of the belt-tight ener withthe part of the machine to which it is applied broken away. Fig. 2 is alongitudinal section oi' the same on the line 2 Q, Fig. 1. Fig. 3 is aplan view of an eccentric used in the belt-tightener. Y 4

This invention is more particularly applicable to arrangements ofmechanism where the chain or belt is driven from a iixed shaft at oneend and at the other end issupported on an idle sprocket or pulley,which can be moved away from the fixed onewsuch, for instance, as incorn-harvesters and similar lmachines where the chains are longand anyintermediate tightener which takes up the slack by throwing a bend intothe chain consumes the power ot' the machine, all of which is needed,and in which class of machines it is desirable that the adjustment ofthe chain shall not materially change its path ot' travel, and therebyinterference with adjoining mechanism will be prevented.

In the drawings, A designates a sprocketwheel, which may be termed anidler and which is designed to be adjusted, by means of thebelt-tightener, so as to tighten such belt. B designates a plate orsupport on a projec tion (t, ol" which the sprocket A is mounted orjournaled and which is secured to the frame O. In the Jframe O oppositethe upper end of this plate isprovided an elongated slot e, and a boltpasses through the hub of the plate, the plateitselif, and the verticalslot in the frame, and its head preferably bears upona washer f' on theinside ot' the frame. If a metal frame is used, the washer is not sonecessary; but with a wooden frame it is particularly desirable. Theouter end oi this bolt bis screw-threaded to receive thereon a nut c,and interposed between the nut c and the end surfaces of hub a,

and the hub of the sprocket-wheel A is a retaining-wash`er u?. Near thelower end of this plate B there is formed a circular aperture, which israbbeted on the lieder side as a matter of convenience,"although, ot'course, this is a detail not essential to the principle of theinvention. A iiXcd bolt 0' has its head bear upon a washer on the insideof the frame and passes through an aperture in said washer and frame andalso through the circular aperture in the plate and through a hole in aneccentric D, which eccentric has its head rabbeted oppositely from therabbet in the plate, so that it may be applied from the under side andits flange bear against the 'liange in the plate and coniine it in thecircular aperture therein while permitting free rotation. A washer 7'may be interposed between the plate and the uut vf, which is shown as awing' or hand nut. This nut engages the outer threaded end of the bolt.17 and serves to secure the plate and 'frame together and act as apivot upon which the eccentric I.) may turn. The l'langed edge ol thiseccentric is marked d', and a handle for inanipulating the same (marked7:) is provided, which preferably is ot' the form shown to adapt it to awrench. Furthermore, this handle is arranged diametrically opposite anaperture fm,l cut in the eccentric I) and through which the bolt f/extends, so aste give the greatest possible throw and the greatestamount ol leverage.

The operation oi' the device above described is as follows: In theposition shown in ifull lines in the drawings the sprocket-wheel has notbeen adjusted and the belt or chain not tightened; but when it isdesired to tighten IOO the belt or chain the operator may with a wrench,such as is usually carried on the machine, loosen the nut c and the nute' (which latter is also provided with means for receiving a wrench aswell as with the wing projections) and may then turn or rotate theeccentric disk D about bolt g/ as a pivot by applying the wrench to thelug or handle 7c on the eccentric disk D, which being eccentricallymounted on the bolt g and operating in the seat formed in plate B toreceive the same causes said eccentric disk D to act as a disk cam tomove or adjust the position of the plate B relative to the frame C, andconsequently of the sprocket A,carried by said plate, and thereby putgreater tension on the belt or chain. It is obvious that when the partsare adjusted if too much tension is found to be placed on the belt orchain it may be relieved by a reverse operation of the eccentric. Thenthe desired adjustment of the sprocket is secured, the operator may holdthe eccentric in place with the wrench and with his other handmanipulate the winged nut until it bears so firmly, through the mediumof the washer, on the plate that all danger of slipping of the sprocketis removed. The wrench may then be removed from the eccentric disk andthe nuts t' and (Z tightened as firmly as may be desired, which willthus etlectually lock the sprocket against movement with respect to thesupport C.

It is manifest that many variations may be made in the details of thedevice described and shown without departing from the principle of theinvention and that many applications of this belt-tightener may be madeother than that particularly suggested herein.

Vhat I claim` and desire to secure by Letters Patent, is

l. In a belt-tightener, the combination with a frame, of a plateadjustably mounted thereon, a sprocket-wheel journaled upon said plate,and an eccentric pivotally mounted upon the frame and arranged to engagesaid plate to adjust the same upon said frame.

2. The combination with a frame, of a plate mounted thereon foradjustment relative thereto, a sprocket-wheel journaled on said plate, abearing formed in said plate, and an eccentric pivotally mounted uponthe frame and operating in said bearing to adjust the position of saidplate.

3. In a belt-tightener, a frame having an elongated slot,a plate mountedupon said frame and carrying a stud or bolt arranged to extend throughsaid slot, a sprocket-wheel supported upon said stud in Jfixed relationwith respect to said plate, a bolt rigidly mounted upon said frame, andan eccentric pivotally mounted upon said last-mentioned bolt andarranged to engage said plate to adjust the same.

4. In abelt-tightener, the combination with an adjustable wheel and aframe, of an eccentric-adjusting device pivoted to the frame andindependent of the wheel and arranged to adjust said wheel;substantially as and for the purpose set forth.

5. In a belt-tightener, the combination with a wheel having' a movablesupport, a frame having an approximately straight and elongated slot forguiding said support, and an eccentric-adjusting device pivotallysupported independent of the wheel -support and ar ranged to engage saidwheel-support to adjust said wheel; substantially as and for the purposeset forth.

6. In a belt-tightener, the combination with a frame having an elongatedapproximately straight slot, a wheel having a support connected theretowhich is guided in said slot, of an eccentric disk, a bolt rigidlymounted in said frame and upon which said disk is pivoted, said diskarranged to engage the wheelsupport to adjust the same; substantially asand for the purpose set forth.

7. In a belt-tightener, the combination with a frame having an elongatedapproximately straight slot, a plate resting against the frame andhaving a projecting hub rigid therewith, a wheel journaled on such hub,a support passing through the hub and through the slot, and aneccentric-adjusting device pivotally mounted upon said frameindependently of said hub and support and arranged to engage said plate,whereby the wheel may be adjusted in right lines; substantially as andfor the purpose set forth.

8. In a bclt-tightener, the combination with a frame having an elongatedapproximately straight slot, a plate bearing on such frame and having aprojecting hub integral therewith, a wheel journaled on such hub, and ashaft or support passing through the hub and slot, of an eccentric diskalso secured to the frame but independently of said hub and support andconnected to operate the plate and thereby adjust the position of thewheel; substantially as and for the purpose set forth.

9. In a belt-tightener, the combination with a frame having an elongatedapproximately straight slot, a plate, a wheel, an eccentric device, saidplate having a bearing for said wheel and an independent bearing forsaid eccentric device mounted thereon; substantially as and for thepurpose set forth.

l0. In a belt-tightener, the combination with a frame having anelongated approximately straight slot, a plate having a bearing-Seatnear the lower end thereof, a wheel journaled on the plate near itsupper end, a shaft o1' support passing through the plate and through theslot in the frame, an eccentric device bean ing in the seat in saidplate, and a pivotbolt connecting such eccentric device to the frame;substantially as and for the purpose set forth.

l1. In a belt-tightener,the combination with a frame, a wheel, a platesupported on the frame and furnishing a bearing for the wheel IOO IIO

substantially as and for the purpose set forth.

l2. In a belt-tig'htener, the combination with a frame, of a plateadjustably mounted on said frame and provided With a bearing, of a Wheeljonrnaled on such bearing, a clampingbolt securing' the plate and frameand adjustable with the plate in said frame, an actuating device, formoving' the plate, pivoted to the frame independently of theWheel-bearing and clamping-bolt, and a locking mechanism formaintaining' the actuating' device in any given position; substantiallyas and for the purpose set forth.

13. In a bel't-tightener, the combination with a frame having anelongated slot, a plate having' a bearing, a Wheel j ournale'd on suchbearing', a bolt passing' through said bearing and through the slot inthe frame, and a nut for clamping these parts in position, of anactuating device for moving the plate and thereby adjusting the positionof the Wheel, a bolt for pivotally securing the actuating' device to theframe independently of the Wheel-bearing' and its clamping-bolt, and acombined winged and wrench nut engaging' the bolt; substantially as andvfor the purpose set forth.

14. In a belt-tightener, the combination with a frame and an adjustableWheel, of an eccentric device having' a handle for moving the same andadapted itself te move the Wheel in its relation to the frame, a boltpassing' through the eccentric device and frame and serving' as a pivotfor such device, and a nut engaging' the end of said bolt and providedwith winged projections and a wrenchholdg substantially as and for thepurpose set forth.

l5. In a belt-tightener,tl1e combination with a frame and a wheeladjustable in said frame, of an eccentric disk provided with a Wrenchhandle or lug' and a pivot passing through the same and the frame, and aloelring-nut provided with Wings and a wrench -hold; substantially asand for the purpose set forth.

16. Ina belttightener, the combination with a frame, a plate adjustablewith reference to such frame and having a bearing' for a Wheel andhaving' a rabbeted recess, of an eccentric disk having a rabbeted edgeadapted to h't the rabbeted recess in the plate, and means for securingsuch eccentric in any position to which it may be put; substantially asand for the purpose set forth.

17. In a belt-tightener,the combination with a frame of a machinehaving' an elong'ated approximateljT straight slot formed therein and anaperture at a little distance therefrom, of a plate having' its facebearing against the frame and having' a projecting stud or hub .servingas a bearing', a wheel mounted upon such bearing', a belt passing'through the bearing' and elongated slot in the frame and bearing'against the reverse thereof by means of its head, a nut engaging threadson the bolt at the other end thereof and serving' to clamp the plate tothe frame when adjusted, said plate also having' a circular recessrabbeted from the underside, an eccentric disk previded with a lug orhandle and a'slot at its op posite periphery and having a rabbeted edgefitting the rabbeted edge of the plate, a bolt passing through such dishand having its head bear against the reverse side of the frame, aclamping-nut having' wings and wrenchhold and bearing against a washer,Which in turn bears against'the disk and the plate and secures them inlixed relation; substantially as and for the purpose set forth.

In Witness whereof I have hereunto set my hand, this 26th day of May,1903, in the presence of the subscribing Witnesses.

FRANKLIN l. BURKHARDI.

Witnesses A. L. Sramana, E. H. KIMBARK.

